Need help with quiz question

Hi, Caroline,

Remember that the foreach loop will loop through each array value. So if it has 4 values, it will loop 4 times. Let's try to go through the code each time the loop runs it. Remember the first line of code inside the foreach loop.

$i = 0;
foreach($numbers as $number) {

    $i = $i + 1;

}

So running through it the first time, $i will be 0 + 1, so when the loop ends the first time, $i = 1. This value will keep stored in this variable for the next loop, so in the second loop, the code will be $i = 1 + 1; So now, $i is equal to 2. Again, this value will be stored in the variable $i. Now the third time, $i = 2 + 1;, which is equal to 3. Now the fourth time, $i = 3 + 1, which is 4. Since the array has only four values, the loop runs only 4 times. So now will know the first time, $i was equal to 1, the second time it was 2, the third was 3 and the fourth was 4.

Now we will go to the second line of code.

foreach($numbers as $number) {

    $i = $i + 1;

    if ($i < $total) {

    $output = $number . $output;

}
}

The if statement says to run the line of code inside it only if $i is less than the $total. Since $total = count($numbers);, it mean that $total is equal to 4, so the if statement says if($ i < 4). Which means it will run until 3. So the conde inside that statement will be executed only 3 times.

Now let's execute that code each time until 3, to see what happens.

In the first time , it will fetch the first value of the array, so $number will be equal to 1. Now the $output will be 1 concatenated to the previous output. Since this is the first loop, the output has no value, so $output = 1 + 0;

$number = 1;
$output = "";
$output = $number . $output;
$output = 1 . "";
$output = 1;

Now that it looped the first time, the value 1 was stored in the output for the next loop. Since it's now the second loop, it will fetch the second value from the array, which is 2, so now $number = 2 and $output = 1, if you concatenate them, $output will be 21.

$number = 2;
$output = 1;
$output = $number . $output;
$output = 1 . 2;
$output = 21;

Now for the third and last time, the value fetched will be 3, so $number = 3 and $output = 21. If you concatenate them, $output will be 321.

$number = 3;
$output = 21;
$output = $number . $output;
$output = 3 . 21;
$output = 321;